Fortunately, the material that Toyota disc brake pads are made from creates the friction necessary to stop your vehicle without any damage occurring to the braking components. There are a set of two disc brake pads in every caliper on the front wheel assemblies of all Toyotas made today and in the recent past. Most vehicles also have pads on the rear as well. These Toyota disc brake pads are forced against the discs which are made of metal. The reason no damage is inflicted on the discs when they come in contact with the disc brake pads is because they are softer. The brake discs are made out of a hardened steel. The disc brake pads are made out of a composite material of ceramics and metallic dust. This composite material is designed and used because when it comes in contact with a metal surface, heat and friction is created. The byproduct is the pads wear down and turn to dust when the brakes are being applied on a Toyota. As these brake components wear, they become thinner. To compensate for this, the piston in the brake caliper has to move further outwards. This space is maintained by hydraulic fluid being transferred from the reservoir in the master cylinder to the caliper. When the fluid level in the brake master cylinder is low, the owner of the Toyota should know that the wear on the disc brake pads is extensive and replacement is required immediately or not too far in the future. If replacement of the pads is not done before they are totally worn out, then the metal backing plate will come in direct contact with the brake rotors causes damage to both components.